Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Fixed Prosthodontics II > Midterm 1 > Flashcards

Midterm 1 Flashcards

1
Q

how is it possible for adhesive resin to bond high noble indirect restorations?

A

Adhesive resin cements work on 4-META technology so you can use it to bond high noble indirect restorations as long as you tin plate the intaglio surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what type of crown should you do with a cast post and core, and why?

A
  • PFM
  • you wouldn’t want to use something like zirconia because you’d get show-through from the CPC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the lingual axial reduction for an anterior PFM preparation for metal? what about porcelain?

A

it is the same for both: 0.5-1.0

*lingual axial reduction is not the same as lingual concavity reduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the areas of importance that you should inspect for detail and accuracy when checking your stone models for crown and bridge?

A
  • prepared tooth/teeth
  • adjacent tooth/teeth, especially proximal surfaces
  • occlusion
  • *you should also check these when inspecting your impression*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what type of margin is used for a cast post and core? what is the purpose of the cast post and core margin?

A
  • bevel margin
  • serves as another ferrule to resist root fracture
  • making the bevel margin isn’t always possible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

For an anterior PFM crown, what is the lingual concavity reduction for metal and porcelain?

A
  • metal lingual - 0.5-1.0mm
  • porcelain lingual - 1.0-1.5mm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Placement of the keyway for a cast post and core is lingual. Why?

A
  • Keeping it lingual can help prevent fracture
  • You have more tooth structures to the lingual
  • It will also prevent the temporary from appearing dark
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

when using triple function articulators, the set should be ___ when the model is poured up

A

passive (tray can’t be torqued or twisted while stone is setting)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

when cutting the die from the cast, why is it important to keep the cuts parallel?

A

So you can put the die back in easily – otherwise you’d have to take off the other pieces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What clinical situations require you to take a full arch impression as opposed to a dual arch impression?

A
  • 2nd molar
  • 3 or more teeth
  • canines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Is it advised to enlarge the canal to create a bigger diameter post to strengthen the restoration?

A

no, never

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is an advantage and disadvantage of having a large base on your die?

A
  • advantage: easier to hold when you are trimming it
  • disadvantage: you will be forced to trim perpendicular to the axis of the preparation at times
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

after trimming the die, what are the next steps up to the point of the wax-up?

A
  • apply 2 coats of die sealer; use compressed air to thin it
  • apply die relief; first coat applied 2-3mm from margins; second coat completely covers first coat and is applied 1-2mm of margins (should NOT touch the margins)
  • begin wax-up
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

T or F:

when trimming the triple tray impression to fit the articulator, opposing sides must be parallel

A

false

they can be somewhat divergent if needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

when pouring up the FGC stone model for the articulator, which arch should be poured up first?

A

the arch with the die

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

If you have a high noble casting (75% gold), can you bond that into place?

A

You can if you tin plate it; you have to bond it with adhesive resin cement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When shaping the die apical to the margin, you want to shape it so that it will maintain ___

A

axial wall contours

you are less likely to abrade the margins if you do this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the difference between a thin and thick biotype?

A

thin biotypes have thinner gingival thickness and are more susceptible to gingival recession, whereas thick biotypes have thicker gingiva and are usually not a problem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what stone type is used when pouring up the FGC stone model for the articulator, and what is it important to remember to do with the articulator before pouring?

A
  • type IV
  • you need to remember to spray silicone separator into the appropriate index of the articulator
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

is the bevel margin on a cast post and core preparation critical?

A

no - it is ideal, but you can still do a CPC if you can’t get the bevel margin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

when taking an impression for a cast post and core, how should the impression material be injected?

A
  • inject around the head of the blue pastic analog post, starting in the anti-rotational keyway
  • move to margins of tooth preparation
  • add balance of syringe material all around the area of the tooth
  • insert the impression tray
22
Q

what type of restoration should be strongly considered on a tooth with more than 1/2 of coronal tooth structure missing?

A

cast post and core

23
Q

which of the following anterior PFM framework designs is/are unfavorable?

  • opposing tooth contacts porcelain
  • opposing tooth contacts the porcelain/metal junction
  • opposing tooth contacts metal
A

opposing tooth contacts the porcelain/metal junction

24
Q

what should you use to finalize the marginal area of your die when trimming?

A

25 blade in a red handle

25
Q

why is the wingless preparation the preferred design for an anterior PFM crown?

A
  • better esthetics
  • slightly less retentive
  • easier
26
Q

why are cast post and cores made with a tapered post?

A
  • because you put a taper on the axial walls of the preparation, and so you want to mirror that
  • it is an indirect restoration and it will be inserted into the tooth, so the taper helps it go in easier because it should match the canal walls
27
Q

what are some important considerations in cementing a final cast post and core restoration?

A
  • post and crown should be cemented simultaneously with a chemical cure, self-adhesive cement such as C&B metabond or panavia
  • vertical pressure should be applied during cementation, and patient should NOT bite on the restoration during the set
  • remove excess cement during the rubbery stage (don’t cause gingival bleeding, and don’t wait until cement is set before removing it)
28
Q

When trimming your die, what is the dangerous direction of the cutting edge to rotate? how can this be avoided?

A
  • Perpendicular to the axis of the die or parallel to the margin
  • Instead, you want the long axis of your cutting instrument to be parallel to the axis of the preparation
29
Q

when taking an alginate impression, you should insert the tray from from front to back or back ro front?

A

front to back

30
Q

Why do we start cutting the cast apart from the base of the index side rather than the die side (aka you go apical to occlusal)?

A

Less chance of having that saw blade come up against the margin

31
Q

If you get anterior gingival recession in someone with a high smile line, is that problematic?

A

yes

32
Q

what should you do to the canal before taking an impression for a cast post and core?

A

dry it with a paper point

33
Q

what is a diagnostic tooth preparation?

A

done before the actual preparation clinically; it gives the operator a preview of what’s coming; it’s kind of like a trial run

34
Q

in the lock-and-key preparation technique, where should the anti-rotational keyway be placed? why?

A
  • on the lingual/palatal aspect
  • it could cause a fracture if it’s not on the lingual
  • it’s more compatible with the forces that are placed on the teeth
  • you tend to have more tooth structure on the lingual/palatal
35
Q

why is it important to extend stone toward the distal when pouring up the stone model of the cast post and core?

A

to create an index, allowing the arches to fit together like a puzzle piece

36
Q

what are the reduction measurements for a FGC?

A
  • occlusal reduction/clearance
    • functional cusp: 1.5-2.0mm
    • non-functional cusp: 1.0-1.5mm
    • functional cusp bevel: 1.5-2.0mm
  • axial reduction: 0.5-1.0mm at margin
  • margin type: chamfer
  • non-functional cusp bevel: 0.3-0.7mm wide
  • softened acute line and point angles
37
Q

What happens if the analog post gets hit when the patient bites down?

A

just trim it

38
Q

for the midterm, what is the range for incisal reduction for an anterior PFM preparation?

A

2-3mm

39
Q

why don’t you need as much lingual reduction for an anterior PFM?

A

Because there is usually metal on the lingual (in other words, you don’t need as much porcelain)

  • lingual concavity reduction for metal is 0.5-1.0mm
  • lingual concavity reduction for porcelain is 1.0-1.5mm
40
Q

T or F:

maxillary keyways should be palatal, and mandibular keyways should be buccal

A

false

they should both be palatal/lingual

41
Q

how should PVS impressions be removed from the patient’s mouth once set?

A
  • opposing arch comes off first
  • remove impression from the prepared tooth arch by pulling entire impression out parallel with the post’s line of draw to avoid torquing or tipping
42
Q

when cementing a temporary crown, why is it important to only apply cement to the base of the acrylic and not on the post?

A

cause you’ll cement the gat dang post to the teeth! then how are ya gonna get it out? SMH.

43
Q

T or F:

You can get a more consistent bite registration component with a triple bite tray (aka dual arch impression) rather than two separate full arch impressions

A

true

44
Q

if a tooth is badly broken down, what type of restoration will hold up best?

A

cast post and core

45
Q

when pouring up the stone model of the cast post and core, which arch should be poured first?

A

the one with the prepared tooth

46
Q

can zirconia crowns be used with any preparation design?

A

yes, even though we have an ideal prep

47
Q

how should vacuum mixers be stored?

A

with water inside

48
Q

In a posterior PFM preparation, what is the axial reduction? where should it be heavier?

A
  • 1.2-1.7mm
  • heavier on buccal transitioning to lighter on the lingual
49
Q

when fabricating a temporary for a cast post and core, why is it important that the metal post is toward the lingual/palatal?

A

if it is too facial, it can show through and give the temporary and darker appearance

50
Q

when doing an impression pour up for a cast post and core, how much stone and how much water should you use? what about when pouring up the FGC stone model for the articulator?

A
  • 100g of stone and 21ml of water for CPC (single arch)
  • 100g of stone and 20ml of water for FGC (two arches, otherwise it’s half for a single arch)
51
Q

what cement should be used on a temporary?

A

polycarboxylate cement

Fixed Prosthodontics II (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions